Add a path for content/ to open and control a Bluetooth chooser dialog.

content/public/browser/bluetooth_chooser.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_PUBLIC_BROWSER_BLUETOOTH_CHOOSER_H_
+#define CONTENT_PUBLIC_BROWSER_BLUETOOTH_CHOOSER_H_
+
+#include <string>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/strings/string16.h"
+#include "content/common/content_export.h"
+
+class GURL;
+
+namespace content {
+
+// Represents a way to ask the user to select a Bluetooth device from a list of
+// options.
+class CONTENT_EXPORT BluetoothChooser {
+ public:
+  class Observer {
+   public:
+    // The user cancelled the chooser instead of selecting a device.
+    virtual void DialogCancelled(int chooser_id) = 0;
+    // The user selected device |device_id|.
+    virtual void DeviceSelected(int chooser_id,
+                                const std::string& device_id) = 0;
+
+    // As the dialog implementations grow more user-visible buttons and knobs,
+    // those knobs will cause new functions to be called here.
+
+   protected:
+    ~Observer() {}
+  };
+
+  // |observer| must outlive |this|. |chooser_id| is propagated to the Observer
+  // methods.
+  BluetoothChooser(Observer* observer, int chooser_id)
+      : observer_(observer), chooser_id_(chooser_id) {}
+  virtual ~BluetoothChooser();
+
+  // Lets the chooser tell the user the state of the Bluetooth adapter. This
+  // defaults to POWERED_ON.
+  enum class AdapterPresence { ABSENT, POWERED_OFF, POWERED_ON };
+  virtual void SetAdapterPresence(AdapterPresence presence) = 0;
+
+  // Lets the chooser tell the user whether discovery is happening. This
+  // defaults to DISCOVERING.
+  enum class DiscoveryState { FAILED_TO_START, DISCOVERING, IDLE };
+  virtual void ShowDiscoveryState(DiscoveryState state) = 0;
+
+  // Shows a new device in the chooser.
+  virtual void AddDevice(const std::string& device_id,
+                         const base::string16& device_name) = 0;
+  // Tells the chooser that a device is no longer available. The chooser should
+  // not call DeviceSelected() for a device that's been removed.
+  virtual void RemoveDevice(const std::string& device_id) = 0;
+
+ protected:
+  // Subclasses call the observer methods through these wrappers, which add in
+  // the chooser ID.
+  void CallDialogCancelled() { observer_->DialogCancelled(chooser_id_); }
+  void CallDeviceSelected(const std::string& device_id) {
+    observer_->DeviceSelected(chooser_id_, device_id);
+  }
+
+ private:
+  Observer* const observer_;
+  const int chooser_id_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_BLUETOOTH_CHOOSER_H_